This invention relates to a liquid refractory binder comprising a tar/pitch and a liquid resin mainly consisting of a resole type phenolic resin compatible with the tar/pitch.
Conventional tar is employed widely for refractory binders but is generally low in the fixed carbon content and rich in volatile substances upon firing. Therefore, it is not suitable as a binder in obtaining refractories with a high density and high strength. Recently, thermosetting phenolic resin binders have been widely employed because they have an advantage in enabling refractories to have a high density and high strength due to their high fixed carbon content even in a low temperature stage of the firing process. However the thermosetting phenolic resin binders have drawbacks. They are costly when compared with tar and pitch. They are poor in oxidization resistance at elevated temperatures.
It is an object of this invention to prepare a liquid refractory resin binder containing a phenolic resin of the resole type which incorporates a tar, pitch or mixtures thereof which will overcome the above drawbacks.
An additional object of the invention is to prepare a high carbon content binder upon use.